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731.
Bone marrow analysis of the myelodysplastic syndromes: histological and immunohistochemical features related to the evolution of overt leukemia 总被引:3,自引:0,他引:3
Masanobu Kitagawa Ryuichi Kamiyama Tamiko Takemura Tsutomu Kasuga 《Virchows Archiv. B, Cell pathology including molecular pathology》1989,57(1):47-53
Bone marrow trephines from 31 patients with an initial diagnosis of myelodysplastic syndromes (MDS) were examined and analyzed histologically and immunohistochemically. In those cases terminating in overt leukemia (6/31, 19%), the number of bone marrow mast cells was significantly reduced, compared with those which did not evolve to overt leukemia. The bone marrow lymphoid cells that may participate in immunosurveillance against the proliferation of blast cells were also significantly reduced in cases terminating in overt leukemia. However, S-100 protein-positive cells, which include histiocytes and suppressor T-cells, were increased in cases terminating in overt leukemia. The results indicated that examination of the bone marrow to determine the proportions of mast cells and lymphoid cells which may be involved in host defense systems may be useful in predicting the evolution to overt leukemia in MDS. In the present series, patients with a hypocellular marrow (5/31, 16%) did not progress to overt leukemia and had a significantly lower bone marrow reticulin content, a significantly lower megakaryocyte count, a relatively higher mast cell count and a significantly higher lymphoid cell count than those with a normocellular or hypercellular marrow. These findings may reflect the initial features of MDS or, possibly, that hypocellular MDS is an independent entity with a low potential for blastic proliferation. 相似文献
732.
Induction of hyper Th1 cell-type immune responses by dendritic cells lacking the suppressor of cytokine signaling-1 gene 总被引:4,自引:0,他引:4
Hanada T Tanaka K Matsumura Y Yamauchi M Nishinakamura H Aburatani H Mashima R Kubo M Kobayashi T Yoshimura A 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(7):4325-4332
Suppressor of cytokine signaling (SOCS1/JAB) has been shown to play an important role in regulating dendritic cell (DC) function and suppressing inflammatory diseases and systemic autoimmunity. However, role of SOCS1 in DCs for the initiation of Th cell response has not been clarified. Here we demonstrate that SOCS1-deficient DCs induce stronger Th1-type responses both in vitro and in vivo. SOCS1-deficient DCs induced higher IFN-gamma production from naive T cells than wild-type (WT) DCs in vitro. Lymph node T cells also produced a higher amount of IFN-gamma when SOCS1-deficient bone marrow-derived DCs (BMDCs) were transferred in vivo. Moreover, SOCS1(-/-) BMDCs raised more effective anti-tumor immunity than WT BMDCs. Microarray analysis revealed that IFN-inducible genes were highly expressed in SOCS1-deficient DCs without IFN stimulation, suggesting hyper STAT1 activation in SOCS1(-/-) DCs. These phenotypes of SOCS1-deficient DCs were similar to those of CD8alpha(+) DCs, and in the WT spleen, SOCS1 is expressed at higher levels in the Th2-inducing CD4(+) DC subset, relative to the Th1-inducing CD8alpha(+) DC subset. We propose that reduction of the SOCS1 gene expression in DCs leads to CD8alpha(+) DC-like phenotype which promotes Th1-type hyperresponses. 相似文献
733.
Fusion proteins with an alpha-hemolysin (HlyA) C-terminal signal sequence are known to be secreted by the HlyB-HlyD-TolC translocator in Escherichia coli. We aimed to establish an efficient Hly secretory expression system by random mutagenesis of hlyB and hlyD. The fusion protein of subtilisin E and the HlyA signal sequence (HlyA(218)) was used as a marker protein for evaluating secretion efficiency. Through screening of more than 1.5 x 10(4) E. coli JM109 transformants, whose hlyB and hlyD genes had been mutagenized by error-prone PCR, we succeeded in isolating two mutants that had 27- and 15-fold-higher levels of subtilisin E secretion activity than the wild type did at 23 degrees C. These mutants also exhibited increased activity levels for secretion of a single-chain antibody-HlyA(218) fusion protein at 23 and 30 degrees C but unexpectedly not at 37 degrees C, suggesting that this improvement seems to be dependent on low temperature. One mutant (AE104) was found to have seven point mutations in both HlyB and HlyD, and an L448F substitution in HlyB was responsible for the improved secretion activity. Another mutant (AE129) underwent a single amino acid substitution (G654S) in HlyB. Secretion of c-Myc-HlyA(218) was detected only in the L448F mutant (AE104F) at 23 degrees C, whereas no secretion was observed in the wild type at any temperature. Furthermore, for the PTEN-HlyA(218) fusion protein, AE104F showed a 10-fold-higher level of secretion activity than the wild type did at 37 degrees C. This result indicates that the improved secretion activity of AE104F is not always dependent on low temperature. 相似文献
734.
Mashima R Saeki K Aki D Minoda Y Takaki H Sanada T Kobayashi T Aburatani H Yamanashi Y Yoshimura A 《The Journal of biological chemistry》2005,280(50):41289-41297
Lipopolysaccharide (LPS) activates macrophages through toll-like receptor (TLR) 4. Although the mechanism of the TLR signaling pathway has been well documented, the mechanism of the negative regulation in response to LPS, particularly LPS tolerance, is still poorly understood. In this study we identified and characterized a novel interferon- and LPS-inducible gene, FLN29, which contains a TRAF6-related zinc finger motif and TRAF family member-associated NF-kappaB activator-related sequences. The induction of FLN29 was dependent on STAT1. The forced expression of FLN29 in macrophage-like RAW cells resulted in the suppression of TLR-mediated NF-kappaB and mitogen-activated protein kinase activation, while a reduced expression of FLN29 by small interfering RNA partly cancelled the down-regulation of LPS signaling. Furthermore, we demonstrated that NF-kappaB activation induced by TRAF6 and TAB2 was impaired by co-expression of FLN29, suggesting FLN29 may regulate the downstream of TRAF6. Taken together, FLN29 is a new negative feedback regulator of TLR signaling. 相似文献
735.
Toshihiko Yanagita Akihiko Wada Ryuichi Yamamoto Hideyuki Kobayashi Tomoaki Yuhi Masanobu Urabe Hiromi Niina 《Journal of neurochemistry》1996,66(3):1249-1253
Abstract: Treatment of cultured bovine adrenal chromaffin cells with 12- O -tetradecanoylphorbol 13-acetate (TPA), an activator of protein kinase C (PKC), decreased [3 H]saxitoxin ([3 H]STX) binding in a concentration (IC50 = 19 n M )- and time ( t 1/2 = 4.5 h)-dependent manner. TPA (100 n M for 15 h) lowered the B max of [3 H]STX binding by 53% without altering the K D value. Phorbol 12,13-dibutyrate (PDBu) also reduced [3 H]STX binding, whereas 4α-TPA, an inactive analogue, had no effect. The inhibitory effect of TPA was abolished when H-7 (an inhibitor of PKC), but not H-89 (an inhibitor of cyclic AMP-dependent protein kinase), was included in the culture medium for 1 h before and during TPA treatment. Simultaneous treatment with TPA in combination with either actinomycin D or cycloheximide, an inhibitor of protein synthesis, nullified the effect of TPA. TPA treatment also attenuated veratridine-induced 22 Na+ influx but did not alter the affinity of veratridine for Na channels as well as an allosteric potentiation of veratridine-induced 22 Na+ influx by brevetoxin. These results suggest that an activation of PKC down-regulates the density of Na channels without altering their pharmacological features; this down-regulation is mediated via the de novo synthesis of an as yet unidentified protein(s), rather than an immediate effect of Na channel phosphorylation. 相似文献
736.
Wataru Mizunoya Yohei Iwamoto Bungo Shirouchi Masao Sato Yusuke Komiya Farzaneh Rahimi Razin Ryuichi Tatsumi Yusuke Sato Mako Nakamura Yoshihide Ikeuchi 《PloS one》2013,8(11)
Dietary fat plays a major role in obesity, lipid metabolism, and cardiovascular diseases. To determine whether the intake of different types of dietary fats affect the muscle fiber types that govern the metabolic and contractile properties of the skeletal muscle, we fed male Wistar rats with a 15% fat diet derived from different fat sources. Diets composed of soybean oil (n-6 polyunsaturated fatty acids (PUFA)-rich), fish oil (n-3 PUFA-rich), or lard (low in PUFAs) were administered to the rats for 4 weeks. Myosin heavy chain (MyHC) isoforms were used as biomarkers to delineate the skeletal muscle fiber types. Compared with soybean oil intake, fish oil intake showed significantly lower levels of the fast-type MyHC2B and higher levels of the intermediate-type MyHC2X composition in the extensor digitorum longus (EDL) muscle, which is a fast-type dominant muscle. Concomitantly, MyHC2X mRNA levels in fish oil-fed rats were significantly higher than those observed in the soybean oil-fed rats. The MyHC isoform composition in the lard-fed rats was an intermediate between that of the fish oil and soybean oil-fed rats. Mitochondrial uncoupling protein 3, pyruvate dehydrogenase kinase 4, and porin mRNA showed significantly upregulated levels in the EDL of fish oil-fed rats compared to those observed in soybean oil-fed and lard-fed rats, implying an activation of oxidative metabolism. In contrast, no changes in the composition of MyHC isoforms was observed in the soleus muscle, which is a slow-type dominant muscle. Fatty acid composition in the serum and the muscle was significantly influenced by the type of dietary fat consumed. In conclusion, dietary fat affects the expression of genes related to the contractile and metabolic properties in the fast-type dominant skeletal muscle, where the activation of oxidative metabolism is more pronounced after fish oil intake than that after soybean oil intake. 相似文献
737.
Akira Uchino Naoki Sentoku Keisuke Nemoto Ryuichi Ishii Muneaki Samejima Makoto Matsuoka 《The Plant journal : for cell and molecular biology》1998,14(5):565-572
Eleocharis vivipara Link alters its photosynthetic mode depending on the growth environment. It utilizes C4 photosynthesis when grown under terrestrial conditions (terrestrial form) and C3 photosynthesis when grown under submerged conditions (submerged form). The photosynthetic organ (the mature internodal region of the culm) of the terrestrial form shows typical Kranz anatomy with well-developed bundle sheath cells, while the bundle sheath cells of the submerged form are not developed. In the mature internodal region of the terrestrial form, expression of the genes encoding two carboxylases, the small subunit of ribulose 1,5-bisphosphate carboxylase (RbcS) and phosphoenolpyruvate carboxylase (Ppc), occurred mainly in bundle sheath cells and in mesophyll cells, respectively, as seen in a typical C4 leaf. In the submerged form, RbcS was expressed in both bundle sheath cells and mesophyll cells, and no expression of Ppc was observed. In the immature internodal region with undeveloped bundle sheath cells, both life forms showed the same expression pattern as in C3 plants: RbcS expression was localized in mesophyll cells and no Ppc expression was observed. The C4-type expression pattern was established concomitantly with the development of bundle sheath cells during tissue maturation in the terrestrial internode. In contrast to the terrestrial form, the submerged form maintains C3-type gene expression during tissue maturation. When the terrestrial culm was submerged, a region of transition from the terrestrial form to the submerged form was established in newly sprouting culms. In this transitional region, C4-type expression of the two carboxylase genes was still maintained even though the development of bundle sheath cells was repressed. This observation suggests that the C4-type cell-specific gene expression pattern does not depend on the formation of Kranz anatomy. 相似文献
738.
Tazawa H Akiyama R Moriya K 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2002,132(4):675-689
Heart rate (HR) in avian embryos developing inside an eggshell has been measured by various means while maintaining adequate gas exchange through the eggshell. This is an important requirement in order to avoid adverse effects of impeding gas exchange on the cardiac rhythms of developing embryos. The present report is a review of our ontogenetic study on embryonic HR, which was measured with fulfillment of the above requirement and also hatchling HR measured non-invasively. Firstly, we reviewed measurements of daily changes (developmental patterns) in embryonic mean heart rate (MHR), which were determined from a short-term measurement of HR once a day, in 34 species of altricial and precocial birds. The allometric relationship between the MHR during pipping in altricial birds and their fresh egg masses was the same as that between the MHR at 80% of incubation duration and fresh egg masses in pre-cocial birds. Secondly, we presented the developmental patterns of MHR in chick embryos and hatchlings, which were determined from long-term, continuous measurement of HR before, during and after hatching. The ultradian and circadian rhythms of HR were clearly shown in embryos and hatchlings, respectively. Thirdly, we summarized instantaneous HR fluctuations: HR variability and HR irregularities, in chick embryos and hatchlings. The distinctive patterns were shown in pre-pipped and pipped embryos and newly hatched chicks, individually, which were partly related to autonomic nervous functions and physiological functions. 相似文献
739.
Yurika Miyoshi Ryuichi Konno Jumpei Sasabe Kyoko Ueno Yosuke Tojo Masashi Mita Sadakazu Aiso Kenji Hamase 《Amino acids》2012,43(5):1919-1931
For elucidation of the regulation mechanisms of intrinsic amounts of d-serine (d-Ser) which modulates the neuro-transmission of N-methyl-d-aspartate receptors in the brain, mutant animals lacking serine racemase (SRR) and d-amino acid oxidase (DAO) were established, and the amounts of d-Ser in the tissues and physiological fluids were determined. d-Ser amounts in the frontal brain areas were drastically decreased followed by reduced SRR activity. On the other hand, a moderate but significant decrease in d-Ser amounts was observed in the cerebellum and spinal cord of SRR knock-out (SRR?/?) mice compared with those of control mice, although the amounts of d-Ser in these tissues were low. The amounts of d-Ser in the brain and serum were not altered with aging. To clarify the uptake of exogenous d-Ser into the brain tissues, we have determined the d-Ser of SRR?/? mice after oral administration of d-Ser for the first time, and a drastic increase in d-Ser amounts in all the tested tissues was observed. Because both DAO and SRR are present in some brain areas, we have established the double mutant mice lacking SRR and DAO for the first time, and the contribution of both enzymes to the intrinsic d-Ser amounts was investigated. In the frontal brain, most of the intrinsic d-Ser was biosynthesized by SRR. On the other hand, half of the d-Ser present in the hindbrain was derived from the biosynthesis by SRR. These results indicate that the regulation of intrinsic d-Ser amounts is different depending on the tissues and provide useful information for the development of treatments for neuronal diseases. 相似文献
740.
Rie Miyamoto Tomoki Ito Shosaku Nomura Ryuichi Amakawa Hideki Amuro Yuichi Katashiba Makoto Ogata Naoko Murakami Keiko Shimamoto Chihiro Yamazaki Katsuaki Hoshino Tsuneyasu Kaisho Shirou Fukuhara 《Arthritis research & therapy》2010,12(3):R87